Dual-listed Jervois is planning a bigger, less staggered restart of its São Miguel Paulista (SMP) refinery, in Brazil, and is considering switching product to nickel sulphate, rather than metal.

The company explained on Monday that nickel sulphate was trading at a significant premium to metal, a trend that was expected to continue, owing to the volume of nickel sulphate forecast to be derived from metal dissolution to satisfy global demand growth.

“Due to strong demand for mixed nickel/cobalt hydroxide products from China’s nickel sulphate refineries, current payables are unfavourable for converting this feedstock into electrolytic nickel and cobalt metal, the ‘tocantins’ product formerly produced at SMP,” said Jervois.

The switch would be linked to restarting SMP at, or close to, its prior capacity of 25 000 t of nickel and 2 500 t of cobalt.

Jervois would work with Ausenco and lead process engineer Metso-Outotec on optimising the scale of the pressure oxidative autoclave to be constructed in front of the existing SMP circuit, to accommodate materials produced by Jervois’ Idaho Cobalt Operations (ICO) in the US and other sulphides.

The company noted that increasing POX capacity would increase capital costs, but that it should lead to improved economics, owing to benefits on metal recovery and operating costs, together with greater feed flexibility.

A completed Ausenco bankable feasibility study would be delivered by the end of the first quarter next year, owing to the flowsheet change with the requisite piloting testwork to support refined nickel sulphate production to be undertaken by Metso Outotec in Finland.

“Jervois remains committed in the attractiveness of restarting SMP, and that a larger, less staggered restart is the correct commercial approach, given the company’s increased scale and market presence following the acquisition of Freeport Cobalt,” it stated.

Meanwhile, Jervois reported that the construction, procurement and engineering schedule for ICO was tracking well with plan and first production of cobalt concentrate from the US mine is expected by the middle of next year.

The company said that, since board approval for full construction in July, more than $30-million had been committed towards equipment, materials and labour costs for ICO.

More than 40% of all equipment and material for the project was committed and Jervois had ordered all long lead items for the processing plant.

US-based M3 Engineering is the engineering, procurement and construction management contractor.

As part of the construction cycle, preparatory works started in the second quarter of 2021.

The project was partially constructed when Jervois acquired it in July 2019, with more than $120-million invested by the previous owners since the discovery of the cobalt deposit.